Crossword Genius

Stays mostly, that is ladies' underwear (8)

Ross

I believe the answer is:

lingerie

I'm a little stuck... Click here to teach me more about this clue!

'ladies' underwear' is the definition.
(I've seen this before)

'stays mostly that' is the wordplay.
'stays' becomes 'lingers' (lingering is a kind of staying).
'mostly' means to remove the last letter.
'that' becomes 'ie' (I am not sure about this - if you are sure you should believe this answer much more).
'lingers' with its last letter taken away is 'linger'.
'linger'+'ie'='LINGERIE'

'is' is the link.

Can you help me to learn more?

(Other definitions for lingerie that I've seen before include "pants! Could be" , "flimsy stuff" , "Women's underwear and nightclothes" , "Female underwear" , "CLOTHING" .)

I've seen this clue in The Telegraph.
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